Hacker News Reader

ViaWeb was re-branded Yahoo Stores, and is still alive and, presumably, healthy.

Of a sort. It was rewritten in C++ and Perl (http://people.csail.mit.edu/gregs/ll1-discuss-archive-html/m...), but is still an active product in its new form.

Even GeoCities is actually still around in the form of Yahoo! Small Business. At least from a technology perspective.